Low back exercise machine with rocking user support

[0001] The present application claims the benefit of U.S. provisional patent application No. 61/310,585 filed Mar. 4, 2010, which is incorporated herein by reference in its entirety.

[0002] 1. Field of the Invention

[0003] This invention relates generally to exercise machines, and is particularly concerned with a low back exercise machine.

[0004] 2. Related Art

[0005] The lower back muscles may be exercised by lying face down on the floor and then lifting the chest from the ground, or by bending down from the waist and then reversing back into an upright position. Lower back muscles can also be exercised using low back exercise machines, which typically have a seat with a rotatably mounted back rest linked to an exercise resistance. The seated user pushes back against the back rest to move it from an upright or forwardly inclined position back into a rearwardly reclined position. In most low back machines, the seat and a foot plate for engagement by the user are stationary during the exercise. This can cause the user to pop up from the seat as they push the back rest and move into a rearwardly reclined position. In some machines, such as the Hoist HS 1225, the seat is linked to the exercise arm so that it tilts rearward slightly to help keep the user from popping out of the seat, but the foot rest is stationary during the exercise. Some machines for exercising the lower back are dual function, combining abdominal and lower back exercises, or low back and leg press exercises.

[0006] A low back exercise machine in one embodiment has a pivotally mounted user support frame carrying a user seat and an adjustable foot rest assembly, an exercise arm carrying a back pad pivotally mounted relative to the user support frame for engagement by a user's back when seated on the user seat, and a connecting linkage which translates movement of the exercise arm into rotation of the user support frame about its pivot axis. An exercise resistance is linked to the exercise arm in one embodiment. In alternative embodiments, the exercise resistance may be linked to resist movement of the user support or connecting link.

[0007] In order to perform the lower back exercise, a user sits on the user support seat with their feet engaging the foot rest, then leans backwards to push against the back pad, rotating the exercise arm rearward about its pivot axis. This in turn rotates the user support frame about its pivot axis via the connecting linkage, so that both the user seat and the foot rest move together as the exercise arm is rotated.

[0008] The combined movement of the user support and exercise arms provides a more comfortable and natural feeling exercise motion that constantly adjusts the position of the user during the exercise to reduce stress on muscles in the low back and groin. The rocking motion of the user support during the exercise also makes the exercise more enjoyable for the exerciser. Since the user's feet track the user support seat as the exercise is performed, there is less risk of the user popping up out of the seat during the exercise.

[0017] Certain embodiments as disclosed herein provide for a low back exercise machine with a rocking user support. Both the user support and the exercise arm move during an exercise, with a connecting linkage translating movement of the exercise arm to rocking movement of the user support so that the user support moves in a predetermined path as the exercise arm rotates rearward during the exercise. In one embodiment, the user support moves forward and upward while the rear end of the user support tilts downward as the exercise arm is rotated rearward by the user.

[0018] After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation.

[0019] FIGS. 1 to 7 illustrate one embodiment of a low back exercise machine 10 for exercising the muscles of the lower back. Machine 10 has a stationary, floor engaging main frame 12, a pivotally mounted user support frame 14, and an exercise arm or user engagement device 15 which is pivotally mounted on the main frame. A conventional weight stack 16 in housing 18 is linked to the exercise arm via a cable and pulley assembly 19 (see FIG. 2). The weight stack and associated connecting struts are omitted in FIGS. 3, 4 and 5 for clarity.

[0020] The main frame has a base portion 20, forwardly inclined rear uprights 22 connected by cross bar or strut 24, and spaced rearwardly inclined front uprights 25 which are connected to the rear uprights 22. Base portion 20 has a pair of side struts 17 extending between the lower ends of uprights 22 and 25, a cross bar 29 extending between the side struts, and a generally central strut 21 extending forwards from cross bar 29. Strut 21 has an inclined end stop face 23 and is supported by an adjustable stabilizing foot 27 at its forward end. As best illustrated in FIG. 7, the weight stack housing is connected to one of the front uprights 25, and is also connected to the main frame base via cable guide tube 26 and to one of the rear uprights 22 via connecting arm 28.

[0021] User support frame 14 has a base support strut 30 with a foot rest assembly 32 adjustably mounted at or adjacent its forward end and an upwardly inclined rear portion secured to a mounting plate 34 on which user seat pad 35 is mounted. A bumper stop 33 extends downward at an angle from base support strut 30 below the foot rest assembly, and engages the end stop face 23 at the forward end of the main frame when the user support is in the start position of FIGS. 1 to 3. Frame 14 also includes a cross bar or strut 36 extending across the back of seat pad 35, and a lumbar pad support plate 38 which extends upwards and rearwards from cross strut 36, as illustrated in FIG. 2. Lumber pad 40 is mounted on support plate 38. Connecting brackets 42 are secured to cross strut 36 and connected to both support strut 30 (see FIG. 1) and support plate 38 (see FIG. 2). A control link 44 is pivotally connected between brackets 42 and the base portion of the main frame. Link 44 is pivoted to the cross strut 24 of the main frame base at its lower end via pivot sleeve 45 rotatably secured between brackets 49 which extend from strut 24, and rotates about pivot axis 46, and is pivoted to the user support brackets 42 at its upper end via a similar pivot sleeve 47 for rotation about pivot axis 48, as best illustrated in FIGS. 2, 3 and 7.

[0022] The exercise arm 15 comprises a generally U-shaped yoke having a central portion 50 and opposite arm portions 52 extending downwardly from central portion 50. Pivot sleeves 53 at the lower ends of the respective arm portions are pivotally connected to pivot mounts 54 at the upper ends of main frame struts 25 for rotation about exercise arm pivot axis 55. A stabilizing handle or grip 57 is secured to each pivot sleeve 53. Back pad 56 is pivotally connected to the central portion 50 of the exercise arm via pivot brackets 58 for rotation about pivot axis 60 so that it adjusts and aligns to the user's back orientation during an exercise.

[0023] As best illustrated in FIGS. 1, 2, 4 and 6, connecting links or brackets 64 are secured to respective exercise arm pivot sleeves 53. End plates 65 at opposite ends of user support cross strut 36 are pivotally connected to the respective connecting links 64 for rotation about user support pivot axis 66. One of the pivot sleeves on the side of the machine closest to the weight stack is also connected to a resistance cam 67 of cable and pulley assembly 19, and weight bearing cable 69 extends from the weight stack through guide tube 26 and around pulleys 70, 71, and from pulley 71 to resistance cam 67. The arrangement is such that the cable is pulled as the exercise arm rotates from the start position of FIGS. 1 to 3 into an end position as in FIG. 4.

[0024] The foot rest assembly 32 comprises a pair of foot rests 72 mounted on the ends of cross bar 74 which is pivotally mounted on a forward end portion of user support strut 30 via pivot links 75, 76. A range of motion adjustment plate 78 (FIG. 3) secured to one side of strut 30 has a series of holes engaged by pull pin adjuster 80 to secure the foot rests in a desired position.

[0025] In order to perform a lower back exercise, a user sits on the user support with the moving parts in the start position of FIGS. 1 to 3, with their low back against lumber pad 40, and their upper back against the user engaging back pad. They then adjust the foot rest assembly to fit their leg length if needed. Next, the user grabs the stabilizing handles 57 for support and leans backwards, putting pressure against the back pad 56 and rotating the exercise arm 15 about pivot axis 55 against the exercise resistance linked to the exercise arm. The connecting links 64 between the exercise arm and user support force the user support to move upward, while the control link 44 between the rear of the user support and the stationary main frame 12 tilts the back end of the user support downward. The result is a compound forward and upward movement of the foot rest and a reclining movement of the seat. The user support seat, lumbar pad, and foot rest are all mounted on the user support frame and fixed at the same relative orientation to one another throughout the exercise, so that the user's feet track the user support during the exercise and the user is in a secure, stable position throughout the movement. This reduces or eliminates the tendency for the user to pop up out of the seat when pushing back into a reclined position.

[0026] In FIG. 5, the start and finish positions of the machine in FIGS. 3 and 4 are overlapped. Part numbers followed by the letter A correspond to the dotted line, start position of the low back exercise machine and part numbers followed by the letter B correspond to the solid line, end position of the machine. As seen in FIG. 5, the user support starts in an upright condition with the user's legs extending approximately horizontally from the seat 35 to the foot rests 72, and the back pad inclined forwards so that the user is bent forward at the waist. As the user pushes the back rest from start position 56A into rearwardly inclined end position 56B, the user support seat 35B is rotated upward about pivot axis 66 while the user support frame is tilted downward at its rear end by the control link 44. This means that the foot rests 72 are raised up from position 72A to position 72B while the seat moves from position 35A to position 35B, and the user's legs remain in line with their body at substantially the same orientation relative to the torso throughout the exercise. The arrangement is such that the base strut of the user support frame tilts upward through an angle of around 17 degrees between the start position 30A and the end position 30B when the back rest is pushed rearward through an angle of around 57 degrees between the start position 56A and end position 56B. It should be understood that end position 56B is not a fixed, predetermined end position, but is controlled by the user based on how much they want to lean back in performing the exercise. The movement pattern between the exercise arm and the user support as controlled by the connecting link and control link reclines the user throughout the exercise so as to exercise the lower back muscles.

[0027] In the above embodiment, movement of the user engagement device or exercise arm is translated into rocking movement of a user support, making the exercise more enjoyable for the user. Additionally, the linked relationship between the movement of the exercise arm and the movement of the user support in the above embodiments is designed so that movement of the user support tracks movement of the exercise arms, with the user support seat moving into a slightly reclined position at the end of the exercise, and the foot rests tracking the movement of the seat. This provides a more comfortable, better feeling exercise that enhances the user's workout.

[0028] It should be understood that all the different elements used in the above embodiment may be mixed and interchanged with one another and still incorporate the essence of the above embodiment. The user support may be mounted on the main frame with the exercise arm pivotally mounted on the user support. The connecting links could be made adjustable and the solid links could be replaced by a cable. Cables could be replaced with belts, ropes, chains, or the like, and pulleys could be replaced with sprockets. The seat could be fixed or made adjustable relative to the supporting frame. Various different types of user engaging pads can be used.

[0029] The pivot mounts may have a single pivot or multiple pivots, and in the latter case the user support pivots about a theoretical pivot mount of the combined pivotal motion. Any of the various embodiments could have the resistance associated with any of the moving parts (user support, user engagement device, or connecting linkage). The exercise resistance may be a weight stack as in the above embodiments, or may be any other type of resistance known in the art, such as weight plates, elastic bands, or pneumatic, electromagnetic, or hydraulic resistance. The exercise machine may be a stand alone machine or may be part of a multi-station gym.

[0030] The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly limited by nothing other than the appended claims.